EP 0993105 A1 20000412 - Control of power transfer in a flyback converter by modulating the off-phase in function of the load
Title (en)
Control of power transfer in a flyback converter by modulating the off-phase in function of the load
Title (de)
Leistungsübertragungssteueurung in Sperrwandler durch lastabhängige Austastmodulation
Title (fr)
Contrôle du transfert de puissance au sein d'un convertisseur Flyback, par modulation de la phase OFF en fonction de la charge
Publication
Application
Priority
EP 98830591 A 19981007
Abstract (en)
A method of controlling a flyback DC-DC converter, self-oscillating at steady state conditions, employing a transformer for storing and transferring energy to a load and having an auxiliary winding whose voltage, induced by the current flowing in the secondary winding of the transformer, is monitored to regulate the amount of energy being transferred by way of a primary control loop disabling and enabling the turning on of a power switch driving the primary winding of the transformer and to detect its the zero-crossing and consequently turn on the power switch for a new conduction and energy storage phase, the duration (TON) of which is established by a secondary control loop of the output voltage producing the turning off of the power switch for a new off phase (TOFF), and comprising a fixed frequency oscillator of a frequency lower than the self-oscillating frequency of the converter for start-up charge transient of an output filter capacitor, wherein the power transferred from the primary circuit to the secondary circuit of the flyback transformer is controlled by introducing a delay on the turn-on instant of the power switch in respect to a turn-on command generated, during a self-oscillating functioning phase upon sensing a zero crossing event and during a fixed frequency functioning phase, upon a rising front of the signal generated by said oscillator, in function of input variables of the enabling-disabling primary control loop and of the secondary control loop, regardless of the mode of control. <IMAGE>
IPC 1-7
IPC 8 full level
H02M 1/00 (2006.01); H02M 1/36 (2007.01); H02M 3/28 (2006.01); H02M 3/335 (2006.01)
CPC (source: EP US)
H02M 1/36 (2013.01 - EP US); H02M 3/33523 (2013.01 - EP US); H02M 1/0032 (2021.05 - EP US); Y02B 70/10 (2013.01 - EP US)
Citation (search report)
- [A] US 5748461 A 19980505 - PRELLER PETER [DE]
- [A] US 5657215 A 19970812 - FAULK RICHARD A [US]
- [A] US 4984145 A 19910108 - DANGSCHAT RAINER [DE], et al
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0993105 A1 20000412; EP 0993105 B1 20030108; DE 69810625 D1 20030213; DE 69810625 T2 20031127; JP 2000125561 A 20000428; JP 4400958 B2 20100120; US 6118675 A 20000912
DOCDB simple family (application)
EP 98830591 A 19981007; DE 69810625 T 19981007; JP 28636299 A 19991007; US 41399699 A 19991007